We have stopped providing support for Akeeba Backup 3.4.3 more than 2 years ago. However, if this problem doesn't occur when you are taking a backup from the back-end of your site then the problem lies with Watchful.li, most likely they fail to see the backup termination message and tell Akeeba Backup to perform one more backup step, effectively restarting the backup.
If the problem does occur when you are taking a backup from the back-end of your site I recommend enabling the "Use database storage for temporary data" and unchecking all the boxes in the Fine Tuning area of the Configuration page of Akeeba Backup.
Nicholas K. Dionysopoulos
Lead Developer and Director
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